organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

2,3-Di­bromo-3-(4-bromo­phen­yl)-1-[3-(4-meth­­oxy­phen­yl)sydnon-4-yl]propan-1-one

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 15 March 2011; accepted 17 March 2011; online 23 March 2011)

In the title compound {systematic name: 4-[2,3-dibromo-3-(4-bromo­phen­yl)propano­yl]-3-(4-meth­oxy­phen­yl)-1,2,3-oxa­dia­zol-3-ylium-5-olate}, C18H13Br3N2O4, the central oxadiazole ring, which is essentially planar with a maximum deviation of 0.016 (3) Å, makes dihedral angles of 29.98 (16) and 52.04 (16)°, respectively, with the terminal bromo-substituted and meth­oxy-substituted benzene rings. An intra­molecular C—H⋯O hydrogen bond generates an S(6) ring motif.

Related literature

For applications of sydnones, see: Rai et al. (2008[Rai, N. S., Kalluraya, B., Lingappa, B., Shenoy, S. & Puranic, V. G. (2008). Eur. J. Med. Chem. 43, 1715-1720.]); Jyothi et al. (2008[Jyothi, C. H., Girisha, K. S., Adithya, A. & Kalluraya, B. (2008). Eur. J. Med. Chem. 43, 2831-2834.]). For details of chalcones, see: Rai et al. (2007[Rai, N. S., Kalluraya, B. & Lingappa, B. (2007). Synth. Commun. 37, 2267-2273.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C18H13Br3N2O4

  • Mr = 561.03

  • Monoclinic, P 21 /n

  • a = 7.8024 (1) Å

  • b = 24.0261 (3) Å

  • c = 10.8211 (1) Å

  • β = 108.848 (1)°

  • V = 1919.76 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 6.33 mm−1

  • T = 296 K

  • 0.39 × 0.27 × 0.13 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009)[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.] Tmin = 0.191, Tmax = 0.496

  • 20615 measured reflections

  • 5841 independent reflections

  • 3490 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.101

  • S = 1.00

  • 5841 reflections

  • 245 parameters

  • H-atom parameters constrained

  • Δρmax = 0.63 e Å−3

  • Δρmin = −0.74 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8A⋯O2 0.98 2.35 3.032 (4) 126

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Sydnones constitute a well-defined class of mesoionic compounds that contain the 1,2,3-oxadiazole ring system. The study of sydnones still remains a field of interest because of their electronic structure and also because of the varied types of biological activities (Rai et al., 2008). Recently, sydnone derivatives were found to exhibit promising antimicrobial properties (Jyothi et al., 2008). Chalcones were obtained by the base-catalyzed condensation of 4-acetyl-3-aryl sydnones with aromatic aldehydes in alcoholic medium employing sodium hydroxide as catalyst at 0–5 °C. Bromination of chalcones with bromine in glacial acetic acid afforded dibromo chalcones (Rai et al., 2007).

The molecular structure of the title compound is shown in Fig. 1. The oxadiazole (N1/N2/O3/C10/C11) ring is essentially planar, with a maximum deviation of 0.016 (3) Å for atom C11. The central oxadiazole ring makes dihedral angles of 29.98 (16)° and 52.04 (16)°, with the terminal bromo-substituted phenyl (C1–C6) and the methoxy-substituted phenyl( C12–C17) rings, respectively.

In the crystal, (Fig. 2), there is an intramolecular C8—H8A···O2 (Table 1) hydrogen bond, which generates an S(6) ring motif (Bernstein et al., 1995).

Related literature top

For applications of sydnones, see: Rai et al. (2008); Jyothi et al. (2008). For details of chalcones, see: Rai et al. (2007). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

1-(31-Phenylsydnon-41-yl)-3-(p-bromophenyl)- propen-1-one (0.01 mol) was dissolved in glacial acetic acid (25–30 ml) by gentle warming. A solution of bromine in glacial acetic acid (30% w/v) was added to it with constant stirring till the yellow colour of the bromine persisted. The reaction mixture was stirred at room temperature for 1–2 hours. The solid which separated was filtered, washed with methanol and dried. It was then recrystallized from ethanol. Crystals suitable for X-ray analysis were obtained from 1:2 mixtures of DMF and ethanol by slow evaporation.

Refinement top

All H atoms were positioned geometrically (C—H = 0.93–0.98 Å) and were refined using a riding model, with Uiso(H) = 1.2 or 1.5Ueq(C). A rotating group model was used for the methyl group.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. The intramolecular hydrogen bond is shown as a dashed line.
[Figure 2] Fig. 2. The crystal packing of the title compound (I).
4-[2,3-dibromo-3-(4-bromophenyl)propanoyl]-3-(4-methoxyphenyl)- 1,2,3-oxadiazol-3-ylium-5-olate top
Crystal data top
C18H13Br3N2O4F(000) = 1088
Mr = 561.03Dx = 1.941 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6367 reflections
a = 7.8024 (1) Åθ = 2.6–28.3°
b = 24.0261 (3) ŵ = 6.33 mm1
c = 10.8211 (1) ÅT = 296 K
β = 108.848 (1)°Plate, colourless
V = 1919.76 (4) Å30.39 × 0.27 × 0.13 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
5841 independent reflections
Radiation source: fine-focus sealed tube3490 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ϕ and ω scansθmax = 30.5°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1111
Tmin = 0.191, Tmax = 0.496k = 3423
20615 measured reflectionsl = 1415
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.0481P)2 + 0.1633P]
where P = (Fo2 + 2Fc2)/3
5841 reflections(Δ/σ)max = 0.001
245 parametersΔρmax = 0.63 e Å3
0 restraintsΔρmin = 0.74 e Å3
Crystal data top
C18H13Br3N2O4V = 1919.76 (4) Å3
Mr = 561.03Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.8024 (1) ŵ = 6.33 mm1
b = 24.0261 (3) ÅT = 296 K
c = 10.8211 (1) Å0.39 × 0.27 × 0.13 mm
β = 108.848 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
5841 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3490 reflections with I > 2σ(I)
Tmin = 0.191, Tmax = 0.496Rint = 0.034
20615 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.101H-atom parameters constrained
S = 1.00Δρmax = 0.63 e Å3
5841 reflectionsΔρmin = 0.74 e Å3
245 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br11.14574 (6)0.038999 (13)0.37333 (4)0.06333 (13)
Br20.95173 (5)0.252012 (13)0.22636 (3)0.05191 (11)
Br30.87928 (7)0.183591 (15)0.60488 (4)0.07974 (16)
O10.9670 (3)0.31433 (8)0.5109 (2)0.0525 (6)
O20.4433 (3)0.22666 (9)0.3829 (2)0.0557 (6)
O30.3565 (3)0.31283 (9)0.4242 (2)0.0513 (5)
O41.0534 (3)0.52989 (8)0.7386 (2)0.0541 (6)
N10.4365 (3)0.36133 (10)0.4786 (2)0.0462 (6)
N20.6087 (3)0.35365 (9)0.5050 (2)0.0347 (5)
C10.9177 (4)0.11794 (11)0.2936 (3)0.0427 (7)
H1A0.81110.13320.23790.051*
C20.9488 (4)0.06109 (12)0.2902 (3)0.0468 (7)
H2A0.86350.03820.23290.056*
C31.1067 (4)0.03920 (11)0.3725 (3)0.0420 (7)
C41.2369 (4)0.07204 (13)0.4552 (3)0.0479 (8)
H4A1.34470.05650.50840.057*
C51.2064 (4)0.12855 (12)0.4587 (3)0.0420 (7)
H5A1.29450.15120.51450.050*
C61.0445 (4)0.15199 (11)0.3793 (3)0.0362 (6)
C71.0097 (4)0.21271 (11)0.3953 (3)0.0337 (6)
H7A1.11850.22930.45700.040*
C80.8505 (4)0.22382 (11)0.4423 (3)0.0395 (6)
H8A0.73810.21210.37550.047*
C90.8350 (4)0.28446 (11)0.4789 (3)0.0374 (6)
C100.6552 (4)0.30218 (11)0.4736 (3)0.0354 (6)
C110.4882 (4)0.27294 (12)0.4223 (3)0.0429 (7)
C120.7239 (4)0.40007 (11)0.5653 (3)0.0342 (6)
C130.8625 (4)0.39242 (11)0.6808 (3)0.0389 (7)
H13A0.88380.35760.72060.047*
C140.9684 (4)0.43718 (12)0.7358 (3)0.0423 (7)
H14A1.06330.43280.81350.051*
C150.9355 (4)0.48902 (11)0.6766 (3)0.0406 (7)
C160.7926 (4)0.49630 (12)0.5621 (3)0.0447 (7)
H16A0.76850.53120.52330.054*
C170.6866 (4)0.45139 (12)0.5062 (3)0.0433 (7)
H17A0.59050.45570.42910.052*
C181.0212 (5)0.58493 (13)0.6871 (4)0.0671 (10)
H18A1.11930.60870.73450.101*
H18B0.91000.59870.69540.101*
H18C1.01260.58440.59660.101*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0987 (3)0.02994 (17)0.0680 (2)0.00875 (16)0.0361 (2)0.00131 (14)
Br20.0698 (2)0.04374 (19)0.04443 (19)0.00350 (15)0.02161 (16)0.00642 (13)
Br30.1518 (4)0.0394 (2)0.0769 (3)0.0121 (2)0.0770 (3)0.01108 (17)
O10.0444 (12)0.0336 (11)0.0857 (16)0.0076 (9)0.0296 (11)0.0153 (11)
O20.0558 (13)0.0399 (12)0.0737 (15)0.0161 (11)0.0243 (11)0.0118 (11)
O30.0404 (12)0.0495 (13)0.0626 (14)0.0055 (10)0.0149 (10)0.0070 (11)
O40.0582 (14)0.0369 (12)0.0598 (14)0.0091 (10)0.0087 (11)0.0069 (10)
N10.0429 (15)0.0402 (14)0.0546 (15)0.0011 (11)0.0145 (12)0.0050 (12)
N20.0362 (13)0.0325 (12)0.0370 (12)0.0008 (10)0.0140 (10)0.0008 (9)
C10.0403 (16)0.0350 (15)0.0506 (17)0.0012 (12)0.0116 (14)0.0072 (13)
C20.0555 (19)0.0331 (15)0.0527 (18)0.0051 (14)0.0187 (15)0.0107 (14)
C30.0583 (19)0.0270 (14)0.0501 (17)0.0016 (13)0.0308 (15)0.0008 (12)
C40.0545 (19)0.0405 (17)0.0468 (18)0.0080 (15)0.0138 (15)0.0036 (14)
C50.0470 (17)0.0357 (15)0.0404 (16)0.0007 (13)0.0102 (14)0.0026 (12)
C60.0432 (16)0.0293 (14)0.0398 (15)0.0002 (12)0.0186 (13)0.0050 (11)
C70.0377 (15)0.0291 (13)0.0360 (14)0.0008 (11)0.0142 (12)0.0021 (11)
C80.0493 (17)0.0288 (14)0.0441 (16)0.0053 (12)0.0202 (13)0.0030 (12)
C90.0457 (16)0.0268 (13)0.0453 (16)0.0017 (12)0.0225 (13)0.0012 (12)
C100.0413 (16)0.0286 (14)0.0397 (15)0.0034 (11)0.0177 (12)0.0007 (11)
C110.0458 (17)0.0410 (17)0.0443 (17)0.0078 (14)0.0178 (14)0.0008 (13)
C120.0389 (15)0.0261 (13)0.0404 (15)0.0007 (11)0.0166 (12)0.0047 (11)
C130.0467 (17)0.0294 (14)0.0410 (16)0.0092 (12)0.0147 (13)0.0059 (12)
C140.0428 (17)0.0390 (16)0.0407 (16)0.0061 (13)0.0074 (13)0.0013 (13)
C150.0457 (17)0.0314 (15)0.0461 (17)0.0012 (12)0.0168 (14)0.0043 (12)
C160.0534 (18)0.0292 (15)0.0476 (17)0.0017 (13)0.0110 (15)0.0037 (13)
C170.0453 (17)0.0361 (16)0.0430 (16)0.0056 (13)0.0067 (13)0.0032 (12)
C180.082 (3)0.0320 (18)0.084 (3)0.0109 (17)0.022 (2)0.0017 (17)
Geometric parameters (Å, º) top
Br1—C31.903 (3)C5—H5A0.9300
Br2—C71.976 (3)C6—C71.504 (4)
Br3—C81.956 (3)C7—C81.510 (4)
O1—C91.211 (3)C7—H7A0.9800
O2—C111.202 (3)C8—C91.525 (4)
O3—N11.362 (3)C8—H8A0.9800
O3—C111.411 (4)C9—C101.449 (4)
O4—C151.364 (3)C10—C111.425 (4)
O4—C181.426 (4)C12—C131.376 (4)
N1—N21.293 (3)C12—C171.376 (4)
N2—C101.363 (3)C13—C141.369 (4)
N2—C121.449 (3)C13—H13A0.9300
C1—C61.384 (4)C14—C151.386 (4)
C1—C21.390 (4)C14—H14A0.9300
C1—H1A0.9300C15—C161.385 (4)
C2—C31.371 (4)C16—C171.375 (4)
C2—H2A0.9300C16—H16A0.9300
C3—C41.367 (4)C17—H17A0.9300
C4—C51.381 (4)C18—H18A0.9600
C4—H4A0.9300C18—H18B0.9600
C5—C61.396 (4)C18—H18C0.9600
N1—O3—C11110.7 (2)Br3—C8—H8A109.8
C15—O4—C18118.0 (2)O1—C9—C10124.1 (2)
N2—N1—O3105.8 (2)O1—C9—C8120.6 (3)
N1—N2—C10114.6 (2)C10—C9—C8115.3 (2)
N1—N2—C12116.0 (2)N2—C10—C11105.1 (2)
C10—N2—C12129.4 (2)N2—C10—C9126.1 (2)
C6—C1—C2120.3 (3)C11—C10—C9128.5 (3)
C6—C1—H1A119.8O2—C11—O3120.2 (3)
C2—C1—H1A119.8O2—C11—C10136.0 (3)
C3—C2—C1119.2 (3)O3—C11—C10103.8 (2)
C3—C2—H2A120.4C13—C12—C17121.9 (3)
C1—C2—H2A120.4C13—C12—N2119.8 (2)
C4—C3—C2121.7 (3)C17—C12—N2118.2 (2)
C4—C3—Br1118.9 (2)C14—C13—C12118.5 (3)
C2—C3—Br1119.4 (2)C14—C13—H13A120.8
C3—C4—C5119.2 (3)C12—C13—H13A120.8
C3—C4—H4A120.4C13—C14—C15120.6 (3)
C5—C4—H4A120.4C13—C14—H14A119.7
C4—C5—C6120.6 (3)C15—C14—H14A119.7
C4—C5—H5A119.7O4—C15—C16124.7 (3)
C6—C5—H5A119.7O4—C15—C14115.1 (3)
C1—C6—C5118.9 (3)C16—C15—C14120.2 (3)
C1—C6—C7122.2 (2)C17—C16—C15119.4 (3)
C5—C6—C7118.8 (2)C17—C16—H16A120.3
C6—C7—C8114.1 (2)C15—C16—H16A120.3
C6—C7—Br2110.67 (18)C16—C17—C12119.5 (3)
C8—C7—Br2105.06 (18)C16—C17—H17A120.3
C6—C7—H7A108.9C12—C17—H17A120.3
C8—C7—H7A108.9O4—C18—H18A109.5
Br2—C7—H7A108.9O4—C18—H18B109.5
C7—C8—C9113.5 (2)H18A—C18—H18B109.5
C7—C8—Br3110.34 (19)O4—C18—H18C109.5
C9—C8—Br3103.54 (18)H18A—C18—H18C109.5
C7—C8—H8A109.8H18B—C18—H18C109.5
C9—C8—H8A109.8
C11—O3—N1—N22.3 (3)C12—N2—C10—C98.6 (4)
O3—N1—N2—C100.6 (3)O1—C9—C10—N21.1 (5)
O3—N1—N2—C12179.6 (2)C8—C9—C10—N2178.2 (2)
C6—C1—C2—C30.2 (5)O1—C9—C10—C11171.4 (3)
C1—C2—C3—C41.9 (5)C8—C9—C10—C119.3 (4)
C1—C2—C3—Br1177.5 (2)N1—O3—C11—O2176.8 (3)
C2—C3—C4—C51.9 (5)N1—O3—C11—C103.0 (3)
Br1—C3—C4—C5177.5 (2)N2—C10—C11—O2177.3 (3)
C3—C4—C5—C60.2 (5)C9—C10—C11—O29.0 (6)
C2—C1—C6—C52.3 (5)N2—C10—C11—O32.5 (3)
C2—C1—C6—C7174.2 (3)C9—C10—C11—O3171.2 (3)
C4—C5—C6—C12.3 (5)N1—N2—C12—C13125.9 (3)
C4—C5—C6—C7174.3 (3)C10—N2—C12—C1352.8 (4)
C1—C6—C7—C860.9 (4)N1—N2—C12—C1752.1 (3)
C5—C6—C7—C8115.6 (3)C10—N2—C12—C17129.2 (3)
C1—C6—C7—Br257.4 (3)C17—C12—C13—C141.7 (4)
C5—C6—C7—Br2126.1 (2)N2—C12—C13—C14179.6 (3)
C6—C7—C8—C9170.7 (2)C12—C13—C14—C150.4 (4)
Br2—C7—C8—C967.9 (2)C18—O4—C15—C164.2 (5)
C6—C7—C8—Br355.0 (3)C18—O4—C15—C14176.5 (3)
Br2—C7—C8—Br3176.43 (11)C13—C14—C15—O4178.2 (3)
C7—C8—C9—O124.4 (4)C13—C14—C15—C161.2 (5)
Br3—C8—C9—O195.3 (3)O4—C15—C16—C17177.7 (3)
C7—C8—C9—C10156.2 (2)C14—C15—C16—C171.6 (5)
Br3—C8—C9—C1084.1 (2)C15—C16—C17—C120.3 (5)
N1—N2—C10—C111.3 (3)C13—C12—C17—C161.4 (5)
C12—N2—C10—C11177.5 (2)N2—C12—C17—C16179.3 (3)
N1—N2—C10—C9172.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···O20.982.353.032 (4)126

Experimental details

Crystal data
Chemical formulaC18H13Br3N2O4
Mr561.03
Crystal system, space groupMonoclinic, P21/n
Temperature (K)296
a, b, c (Å)7.8024 (1), 24.0261 (3), 10.8211 (1)
β (°) 108.848 (1)
V3)1919.76 (4)
Z4
Radiation typeMo Kα
µ (mm1)6.33
Crystal size (mm)0.39 × 0.27 × 0.13
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.191, 0.496
No. of measured, independent and
observed [I > 2σ(I)] reflections
20615, 5841, 3490
Rint0.034
(sin θ/λ)max1)0.715
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.101, 1.00
No. of reflections5841
No. of parameters245
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.63, 0.74

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···O20.982.353.032 (4)126
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
First citationBruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationJyothi, C. H., Girisha, K. S., Adithya, A. & Kalluraya, B. (2008). Eur. J. Med. Chem. 43, 2831–2834.  Web of Science PubMed Google Scholar
First citationRai, N. S., Kalluraya, B. & Lingappa, B. (2007). Synth. Commun. 37, 2267–2273.  Web of Science CrossRef CAS Google Scholar
First citationRai, N. S., Kalluraya, B., Lingappa, B., Shenoy, S. & Puranic, V. G. (2008). Eur. J. Med. Chem. 43, 1715–1720.  Web of Science PubMed Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds